For patients with varying degrees of spondylolisthesis, degenerative disc disease, and/or nerve compression with associated lower back pain, spinal fusion surgery, or lumbar arthrodesis, is an effective and commonly used treatment. Spinal fusion surgery involves distracting or decompressing one or more intervertebral spaces, removing the associated disc(s), and joining or fusing two or more adjacent vertebrae together using a bone graft and/or spinal implant. The five main types of lumbar arthrodesis include: posterior lumbar fusion (PLF), posterior lumbar interbody fusion (PLIF), anterior lumbar interbody fusion (ALIF), circumferential 360 fusion, and TLIF.
PLF, utilizing a back (posterior) approach, with pedicle screws, plates, or the like is relatively simple, safe, and allows for good posterior decompression. However, it does not remove the disc or immobilize the segment very effectively. PLIF, also utilizing a back (posterior) approach, with pedicle screws, plates, or the like removes the disc and immobilize the segment effectively, but nerve roots may be moved and damaged, and there is a risk of neural lesions. ALIF, utilizing a front (anterior) approach, with pedicle screws, plates, or the like also removes the disc and immobilize the segment effectively, but again nerve roots and blood vessels may be moved and damaged, and there is a risk of neural lesions. Circumferential 360 fusion, utilizing a back-and-front approach, combines the advantages and disadvantages of the posterior and anterior methods.
In recent years, many spinal surgeons have begun to use TLIF instead of PLIF or other methods. The main advantage of TLIF over PLIF and other methods is that it allows for complete removal of the disc through the vertebral foramen and decompression of the spinal canal and vertebral foramen with minimum risk of neural lesion, as access is lateral to the nerve roots.
Conventional TLIF inserter devices are fixed, static devices that are mutually exclusively either substantially curved (in order to minimize tissue disruption during initial spinal implant placement and subsequent positioning) or substantially straight (in order to maximize inline impaction forces during final spinal implant positioning). Thus, what is needed in the art is a TLIF inserter device that is flexible and dynamic, and that is alternatively substantially curved to minimize tissue disruption and substantially straight to maximize inline impaction forces.